The sketch of a meandering stream below shows various positions of the stream over time. Which is the correct time sequence for the various positions of the stream?
1) Position 1, Position 2, Position 3, Position 4
2) Position 4, Position 3, Position 2, Position 1
3) Position 1, Position 3, Position 2, Position 4
4) Position 4, Position 2, Position 3, Position 1